schroeder



Aug. 18, 1959 c. s. SCHROEDER CONCEALED DOOR CLOSER 5 Sheets-Sheet 1 Filed May 10, 1954 N 6 Qv on 3 Mn B ATTORNEY Aug 18, 1959 c. s. SCHROEDER CONCEALED DOOR CLOSER Filed May 10. 1954- 5 Sheets-Sheet 2 2 fiflhw 1i fi m nw :TIJ m mm 0 Fir \E i A). 15%? M5.. m 8 on 5 m T a. Q @v in mm 0m o 8 mm M m hi 5 g c. 9 on ATTORN EY 8, .1959 c. s. SCHROEDER 2,899,701

'QONCEALED DOOR CLOSER Filed May 10. 1954 5 Sheets-Sheet 4 ATTORNEY Aug. 18, 1959 c. s. SCHROEDER CONCEALED DOOR CLOSER Fil ed May 10. 1954 llllllllllflmmlll lllilmmllll 5 sheets-sheet 5 INVENTOR C- aAPaeQ e ATTORNEY United States Patent fifice 2,899,701 Patented Aug. 18, 1959 2,899,701 CONCEALEDDOOR CLOSER Charles S. Schroeder, Wynnewood, Pa., assignor to The Yale & Towne Manufacturing Company, Stamford, Conn., a corporation of Connecticut Application May 10, 1954, Serial No. 428,398 9 Claims. (CI. 16-64) This invention relates to door closers of the type adapted to be mounted within a hollow upper" rail of a door. Certain problems arise in constructing door closers of this type because the door rail offers only a narrow space in which to mount the closer. Naturally, to fit within the space in the door rail, the door closer mechanism must be arranged in a casing that is quite narrow. It is difiicult, while meeting this condition, to construct a door closer that can be adjusted to operate properly and that will have the desired operating characteristics. Moreover, there are now in use doors constructed with a very slender upper rail. Sometimes these doors are principally of glass, and it is then important for the sake of appearance that the upper rail be made as slender as is practicable. Obviously, the space that is available in the upper rail of such doors is not only narrow horizontally, but also very limited in depth, and a very considerable problem is involved in constructing a satisfactory door closer to be concealed within the rail.

I have now conceived an extremely novel construction for a door closer that is slender and well adapted for doors of that particular type. Notwithstanding the slender form of my door closer, I do not sacrifice the effectiveness of the closer mechanism, and I actually enable this mechanism to function very efficiently. It is possible to utilize my novel closer successfully on a door of the type having an upper rail that is exceedingly slender, with the closer concealed within the rail. Moreover, in my invention I utilize between the door closer and the door frame a linkage that is concealed when the door is in closed position, thereby enhancing further the appearance of the door.

The mechanism of my novel door closer is of the type including as its principal parts a coil spring, a rack and pinion through which the coil spring acts to close the door, and a dashpot for opposing the spring action. These parts are arranged in longitudinally aligned relation in a very slender casing, with the spring and dashpot acting against opposed ends of the rack. An arm is fixed relatively to the pinion outside the slender casing, and is adapted to be connected with the door frame through a link whereby to rotate the pinion with the opening and closing movements of the door. I contribute novel means for adjusting the position of the door closer arm relatively to the slender casing, and I contribute also extremely novel features whereby the spring and dashpot can operate in the very slender casing without a tendency to bind in this casing.

As an important feature of my invention, I effect adjustment of the door closer arm through adjustment of the closer casing longitudinally in the hollow upper rail of the door. For the particular purpose, I utilize adjust ing means engaged between one end of the casing and a part on the door, and acting through the casing to shift the axis on which the closer arm rotates. By shifting the arm axis in this way, with the arm connected to the door frame through the link, I adjust the position the arm occupies relatively to the casing when the door is closed.

2 I prefer to utilize for the adjusting means a screw that is arranged to be accessible at the edge of the door, and through this screw I can very readily adjust the closer arm to occupy a position aligned with the rail of the door when the door is in closed position.

As another feature of my invention, I mount the rack to float so that the rack is not directly supported on the casing, but I nevertheless arrange a direct bearing engagement between the rack and casing to hold the rack meshed with the pinion. I am enabled through this arrangement to obtain very satisfactory operation of the closer while the spring and dashpot are mounted in aligned relation in the extremely slender casing, and without causing the rack to bind in the casing. More particularly, I support the rack at one end upon the dashpot piston, and at the opposed end upon a guide member sliding on a lower surface in the casing. The rack has a relatively Wide surface sliding upon one inner side of the casing, but this side of the casing is flat whereby to allow the rack to float on the piston and guide member. The flat side of the casing then acts merely to hold the rack meshed with the pinion, while the pinion holds the rack relatively to the flat side and away from the opposed side of the casing.

As a further particular feature, I construct the rack to operate in a relatively small space between one side of the pinion and that side of the casing against which the rack bears. I am able to make the rack quite thin, because this side of the casing. is flat and I can make the rack wide in a vertical direction. Also, I reinforce the rack through a member attached to both ends of the rack. This member extends through anarrow space between the pinion and the opposed side of the casing, but moves freely in this narrow space because it is held by the rack out of contact with both the pinion and the casing.

As a detailed feature of the invention, I so form the closer casing as to have at least two opposed flat sides, with the casing preferably rectangular in shape. I thereby utilize to best advantage the space within the slender door rail, and I am able to mount in the casing a rack and a pinion that are large relatively to the width and depth of the space in the hollow door rail. As a further feature of this part of the invention, I contribute novel means for covering the opening through which the large pinion is assembled in the casing.

Another feature of my invention resides in means whereby I guide and hold the door closing spring out of contact with the inner surface of the slender casing. For the particular purpose, I equip the rack with a spring guide moving with the rack and extending in an axial direction relatively to the spring. Preferably, a loose connection supports this spring guide at one end on the rack whereby the guide does not interfere with the floating action of the rack in the casing, telescoping means then being provided to support the opposed end of the spring guide on the casing.

As a further feature, I contribute novel closure means for the door closer casing. The main portion of the easing is merely a relatively thin-walled tube having flat sides, and for closing one end of this tube I provide an end member that is flat sided to fit within the tube end. I mount a resilient ring in a groove in the end member, and I particularly form the periphery of this ring with fiat sides to conform to the shape of the tube whereby to seal the end member relatively to the tube.

I have thus outlined rather broadly the more important features of my invention in order that the detailed description thereof that follows may be better understood, and in order that mycontributio'n to the art may be better appreciated. There are, of course, additional fea tures of my invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception on which my disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of my invention. It is important, therefore, that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of my invention, in order to prevent the appropriation of my invention by those skilled in the art.

Referring now to the drawings:

Fig. 1 is a plan view showing my novel door closer installed in a door.

Fig. 2 is a front view of Fig. l, with the door rail in section.

Fig. 3 is similar to Fig. 1, but shows the door in open posltion.

Fig. 4 is a cross-section of the closer on the line 44 of Fig. 6.

Fig. 5 is a plan view of the door closer with the closer arm removed.

Fig. 6 is a longitudinal section of my closer.

Fig. 7 is a section on the line 7-7 of Fig. 6.

Fig. 8 shows the sealing ring that I utilize at one end end of my door closer.

Fig. 9 is similar to Fig. 1, but illustrates different adjusted positions of the door closer.

Fig. 10 illustrates diagrammatically the dashpot of my door closer.

Fig. 11 shows parts of the closer mechanism in exploded relation.

To enable my invention to be readily understood, 1 illustrate in Figs. 1, 2, and 3 a portion of a door having an upper rail 10 that is very slender, with a preferred form of my novel door closer mounted within this rail 18. I show the closer connected to the door frame 11, and I indicate at 12 the pivot member on which the door rotates relatively to the frame. The upper door rail 10 is open at its top, being formed as a channel, but because of its very limited width and depth offers little space in which to mount the closer. I form the door closer to fit rather closely within the space in the rail 10, and for the particular purpose, I utilize as a main portion of the closer casing an elongated narrow tube 13 that is square in section, as best seen in Fig. 4.

Referring particularly to Fig. 6, I equip the square tube 13 at one end with a member 14, this member having a square portion 15 fitting within the tube 13 and welded to it whereby to close this end of the tube. I form the portion 15 of the end member with a longitudinal bore 16 to serve as a dashpot cylinder, which I shall describe in due course. I provide also an end member 17 having a square portion 18 fitting within the opposed end of the tube 13. I make the end member 17 removable in order to facilitate the assembly of the door closer, and to secure this member to the tube 13 I prefer to utilize vertical cross pins 19, Figs. 1 and 6, these pins being retained by cotter pins 20. To seal the end member 17 relatively to the tube 13, I utilize an extremely novel resilient ring 21, Figs. 6 and 8. This ring 21 is formed with a square periphery whereby to conform to the inner surface of the square tube 13, and has a circular opening whereby to be mounted in a circular groove 22 in the end member 17. Through this construction, I enable the end member 17 to be very readily assembled and disassembled relatively to the closer, while at the same time enabling the square tube 13 to be completely sealed.

I mount the closer in the slender door rail 10 through the opposed end members 14, 17 of the closer casing,

as clearly indicated in Fig. 1, whereby to enable the end members 14, 17 of the casing to seat upon these bars. Each bar 24 has a vertical stud 25 to be positioned in the corresponding bore 23, but these studs have a diameter" much smaller than the bores 23 to allow the closer casing to be adjusted in a longitudinal direction in the door rail. I equip the studs 25 with relatively large washers- 26, and with nuts 27 adapted to draw the washers 26 against the upper surfaces of the end members 14, 17 to hold the door closer seated on the bars 24 in the door rail. 1

I provide the end member 14 of the door closer with a screw 28 for adjusting the closer longitudinally on the seating bars 24. This screw 28 projects in an axial direction from the end member 14, and is formed with a shoulder 29 adapted to seat relatively to a vertical part 30 on the pivoted edge of the door, as well shown in Fig. 1. A slotted end 31 on the screw 28 is positioned in an opening through the edge of the door so that the screw is easily accessible, and by rotating the screw 28, the closer casing can be shifted longitudinally in the door rail 10. The nuts 27 can be somewhat loosened on the studs 25 if this is necessary to permit the adjustment of the closer. I prefer to equip the end member 14 with a set screw 32 for holding the screw 28 in adjusted position.

Because my door closer can be adjusted longitudinally on its mounting in the door rail 10, I am able to utilize a novel arrangement for connecting the closer to the door frame, as I shall now explain. Referring particularly to Figs. 1, 2 and 3, the tubular casing 13 of the closer has avertical pinion shaft 33 through which the closer acts, and this pinion shaft 33 has a square upper end 34 upon which a closer arm 35 is secured by a screw 36. A link 37 is pivoted at one end of the arm 35 by a pivot 38, and is adapted to be pivoted at its opposed end to the door frame 11, thereby causing the pinion shaft 33 to rotate with the opening and closing movements of the door. For pivoting the link 37 to the door frame 11, I show a pivot 39, Figs. 1, 2 and 3, mounted on the frame through a bracket 40, but the details of this pivot and its mounting on the frame 11 are not important to an understanding of my invention. Referring particularly to Fig. 2, it will be observed that I make the pinion shaft 33 relatively short, with the closer arm 35 and link 37 rather closely juxtaposed to the fiat upper surface of the tubular casing 13. When the door closer is mounted in the door rail 10, the closer together with its arm 35 and link 37 are actually below the upper edge of the rail, as best seen in Fig. 2, with the link 37 positioned at the lower side of the door frame 11 on the pivot 39.

Moreover, I arrange the closer arm 35, and a major part 41 of the link 37 as well, to be aligned with the door rail 10 when the door is in closed position as shown in Fig. 1. Of course, when the door opens, the closer arm 35 and link 37 move out of aligned relation to the door rail, as in Fig. 3, and to permit this movement I cut away a narrow edge part 42 on one side of the rail 10, as best seen in Fig. 2. The aligned arrangement of the arm, link and door rail does, of course, depend upon the relation between the axis of the pinion shaft 33 and the axis of the pivot 39 on the door frame when the door is closed, and any change in this relation will cause a change in the position of the closer arm 35. This may be best understood from a consideration of Fig. 9, in which I illustrate the closer arm 35 in two difierent positions corresponding to different positions of the pinion shaft 33. Actually, because of the extremely slender form of the door rail 10, the position of the shaft 33 relatively to the pivot 39 is quite critical. To enable me to establish easily the proper relation between the shaft 33 and pivot 39, I utilize the longitudinal adjustment of the door closer, that I have already described. Thus, once the door closer is assembled in the door rail 10, with its link 37 pivoted to the door frame 11, I can utilize the screw 28 to adjust the closer casing longitudinally and thereby to shift the axis of the shaft 33. By adjusting the shaft axis to a particular position relatively to the axis of the pivot 39 on the door frame, I cause the closer arm 35 to occupy a position aligned with the casing 13 of the door closer when the door is closed. The entire door closer, excepting for a small part of the link 37, is then within the upper rail of the door. Through the novel construction that I have thus far described, I enable the closer arm and link to act when the door closer is mounted within a slender door rail and I am able, furthermore, to conceal the closer when the rail is extremely slender.

I shall now proceed to describe more particularly the mechanism that I utilize in my extremely novel door closer, referring to Figs, 6, 7, and 11. Fixed upon the pinion shaft 33 inside the tubular closer casing 13 is a pinion 43, this pinion preferably being formed integrally with the shaft. Because of the square shape of the casing 13, I am able to make the pinion 43 relatively large. I mount the shaft 33 to rotate in the casing 13 through needle bearings 44, 45 encircling the shaft above and below the pinion 43, and I utilize a particular mounting for the upper needle bearings 44 to enable the relatively large pinion 43 to be assembled in the casing 13. Thus, I support the upper needle. bearings 44 through a bushing 46, Fig. 6, fixed in a wide opening in the flat upper side of the casing 13. This bushing is nearly as wide as the casing 13, and has a large bore through which the pinion 43 can be inserted into the casing. When the pinion 43 is in assembled position, a spacer sleeve 47 is inserted into the large bore in the bushing 46 to hold the upper bearings 44.- To support the lower bearings 45, I utilize merely a cup member 48 fixed in an opening in the lower fiat side of the casing 13.

In order to cover the upper bearings 44 and to close the large opening in the bushing 46, I utilize an extremely novel cap 49, well shown in Figs. 4, 5, and 6. This cap 49 has a central opening through which the pinion shaft extends, and is practically as wide as the casing 13 whereby to seat upon the flat top of the casing 13 around the bushing 46. However, projecting outwardly from opposed sides of the cap 49, I form a pair of lugs 50. Through rotation of the cap 49, the lugs 50 are adapted to engage under clips 51 secured to the upper surface of the casing 13 by screws 52, thereby holding the cap seated on the casing. I particularly align the clips 51 relatively to the longitudinal axis of the casing 13 whereby the lugs 50, when engaged under the clips 51, are in aligned relation to the casing. I thereby contribute extremely simple means that cover the relatively wide bushing 46 without projecting beyond the sides of the casing. I do, incidentally, prefer to utilize the cap 49 to retain a resilient O-ring 53 to seal completely the opening in the bushing 46.

A rack 54 extends in the relatively narrow space between the pinion 43 and one flat side 55 of the square casing 13, and is meshed with the pinion so as to move longitudinally as the pinion rotates. The rack 54 has transverse end portions 56, 57 well shown in Figs. 7 and 11, and I reinforce the rack through a plate 58 attached integrally to these end portions 56, 57 to extend intermediate the pinion 43 and the opposed flat side 59 of the casing 13. For attaching the plate 58, I prefer to utilize tongues 60 formed on the opposed ends of the plate, as best seen in Fig. 11, and secured in slots 61 in the end portions 56, 57 of the rack. Because the opposed sides 55, 59 of the casing 13 are flat, I am able to make the rack 54 and reinforcing plate 58 relatively wide in a vertical direction, with the rack 54 arranged to slide on the casing side 55 over a wide fiat surface. In this arrangement, the pinion 43 and easing side 55 hold the rack 54 relatively to one another, and by the particular form of the rack the reinforcing plate 58 is then out of contact with both the pinion and the opposed flat side 59 of the casing.

answer 6 Actually, the rack 54 is out of contact also with the top and bottom sides of the casing 13, as shown in Fig. 6, and to support the rack in this relation I utilize extremely novel means including a piston 62 in the dashpot cylinder 16 at one end of the rack, and a guide member 63 in the casing 13 at the opposed end of the rack. The piston 62 is relatively long whereby to be self-aligning in the cylinder 16, and is cup-shaped in form. Fixed on the end portion 56 of the rack is a piston rod 64 extending axially into the cup-shaped piston 62, and the end of this rod 64 has a surface 65 seated against an inner surface in the piston 62. Thus, when the fluid in the dashpot cylinder 16 opposes movement of the piston 62, as will presently be described, the piston acts positively through the end surface 65 on the rod 64 to control the action of the door closer. A spiral spring 66 encircles the rod 64 and is engaged between a shoulder 67 on the rod 64 and a groove 68 in the inner surface of the piston 62 whereby to hold the rod and piston assembled to one another. It is important to observe here that the spirai spring 66 by yielding enables the rod 64 and rack 54 to have a certain lateral movement relatively to the pisston 62.

I form the guide member 63 as a block having a sliding fit between the top and bottom of the square casing 13, but somewhat narrower than the casing, as well shown in Fig. 4. In one face of the guide member 63 is a horizontal groove 69, Figs. 6 and 11, in which the end portion 57 of the rack 54 is positioned. Thus, the guide member 63 supportsthe particular end of the rack 54, but does not control the transverse position of the rack. Of course, the rack 54 is engaged with the fiat side wail 55 of the casing 13, but this wall 55 offers no support to the rack in a vertical direction. It will be seen, therefore, that the rack 54 floats in the casing 13 on the guide mernber 63 and piston 62.

For actuating the rack 54 in a door closing direction, I utilize a coil spring 70, Fig. 6, pressing at one end against the guide member 63 and at its opposed end against the closure member 17 of the casing. Actually, this coil spring 70 is seated on the guide member 63 and holds this member in assembled relation to the end portion 57 of the rack. To guide the spring 70 in the square tubular casing 13, I mount upon the rack a spring guide 71. This spring guide 71 is preferably tubular in form and is assembled loosely at one end upon a stud 72 formed integrally with the end portion 57 of the rack. In this arrangement, the tube 71 extends through an opening 73 in the guide member 63 and is held relatively to the rack through a flange 74 extending between the rack and guide member. As will be clearly understood from Fig. 6, the tubular guide 71 extends axially within the coil spring 70 and holds the spring out of contact with the fiat sides of the casing 13. To support the coil spring 70 throughout its length, I prefer to equip the end casing member 17 with a rod 75, this rod having a threaded connection 76 with the end member 17 and extending into telescop ing relation with the tubular spring guide 71.

Those skilled in the art will understand that fluid in the dashpot cylinder 16 controls the door closing movement of the piston 62. For the purposes of this disclosure, I show diagrammatically in Fig. 10 the means whereby I control this fluid. Thus, I equip the dashpot cylinder 16 with a passage 77 leading from the end of the cylinder to the interior of the casing 13. I provide also a passage 78 leading from an intermediate point in the cylinder 16 to an intermediate point in the passage 77. I equip the passage 77 with a needle valve 79 between the passage 78 and the interior of the casing, and also with a needle valve 80 between the passage 78 and the end of the cylinder 16. The inner surface of the cylinder 16 has a circular groove 81 through which the passage '78 communicates with a circular groove 82 in the piston 62 when the piston is in an intermediate position in the cylinder,

this groove 82 being in communication with the interior of the casing 13 through an opening 83 in the piston. I show at 84 a passage with a check valve 85 that allows the fluid to pass freely from the casing to the cylinder 16 when the piston 62 moves in a door opening direction, the check valve 85 being closed during the door closing movement, as will be understood. In operation, the closer spring 70 acts through the rack 54 to move the piston 62 toward the end of the dashpot cylinder 16, with the fluid thus displaced from the cylinder forced through the passage 78 and needle valve 79 to the interior of the casing, it being understood that the liquid is free to flow also through passage 77. When the piston 62 moves to a position closing the groove 81 in the cylinder, the fluid must move through the passage 77 past both needle valves 8% and 79, thereby controlling the movement of the piston by valve 80, as well as valve 79. As the groove 82 in the piston comes into aligned relation to the groove 81 the fluid need move only through the needle valve 30, thus enabling the spring 70 to move the door to latching position under the control of valve 80 alone. It will be understood, of course, that I prefer to form the passages 78 and 79 integrally in the end member 14 of the closer casing, with the needle valves 79 and 89 mounted in this member as illustrated, for example, in Figs. 1 and 6.

I believe that the very considerable advantages of my extremely novel door closer will now be understood. I am enabled by my invention to arrange the dashpot, rack, and spring in aligned relation in an extremely slender casing, and through the floating mounting of the rack and spring relatively to the casing and relatively to one another I avoid any tendency of the closer mechanism to bind in the very slender casing. The closer mechanism, while mounted in a very limited space, is nevertheless sturdy and dependable. In addition, through the novel construction of the closer, I am enabled easily to mount the closer within an extremely slender upper rail of a door with the closer arm arranged to be concealed in the rail when the door is in closed position. I believe, therefore, that those skilled in the art will appreciate fully the considerable value of my invention.

I new claim:

1. In a door closer of the class described, a narrow tubular casing formed with a flat side, a pinion, said tubular casing having through said flat side an opening extending across a major part of the width of the casing to enable the pinion to be assembled in the casing, a shaft portion on said pinion, bearings mouting said shaft portion to rotate in said opening with the pinion in said casing, means for rotating the shaft portion and pinion during the opening and closing movements of a door, a cap encircling said shaft portion and of relatively large diameter whereby to close said opening, a pair of lugs projecting from opposed sides of said cap, a pair of clips on the casing with which said lugs are engaged through rotation of the cap whereby to hold the cap seated on said flat side of the casing, and said clips aligned longitudinally on the casing whereby the lugs when engaged with the clips do not project beyond op posed sides of the casing.

In a door closer of the class adapted to be mounted in a hollow upper rail of a door, an elongated casing having an internal longitudinal chamber formed with a longitudinal bearing surface, a rack Within said casing chamber and having a bearing surface adapted to slide on the said longitudinal bearing surface of said casing chamber, a cylindrical piston mounted in a cylindrical opening in said casing communicating with said longitudinal chamber, means connecting said piston to one end of the said rack, including yielding means through which said piston floatingly supports said one end of said rack in the chamber, a guide member mounted on the opposed end of the rack and movable within said casing for floatingly supporting the opposed end of the rack for sliding in the chamber with said rack spaced from all surfaces of said chamber except said longitudinal bearing surface, a closer pinion rotatably mounted in said chamberin meshed relation to the rack, and apart of the pressure incidental to the'meshing of said closer pinion and rack being'accepted by the bearing surface of said rack pressing against the longitudinal bearing surface of said chamber.

3. In a door closer of the class described adapted to be mounted in a hollow upper rail of a door, an elongated tubular casing formed with a longitudinal flat side, a rack having a bearing surface adapted to slide on the inner longitudinal surface of said flat casing side, a piston adapted to slide in an opening in the casing, means connecting said piston to one end of said rack including. means through which said piston fioatingly supports said one end of therack while sliding with said rack in the casing, a coil spring acting against the opposed end of said rack, a spring guide connected to the rack and extending in aligned relation to said coil spring, a guide member movable in the casing and supporting said opposed end of the rack to float in the casing, said guide member supporting the spring guide in position to hold the spring away from the inner surfaces of the tubular casing, acloser pinion rotating in the casing in meshed relation to the rack, and said closer pinion pressing the rack to hold its bearing surface against the flat casing side as the rack floats on the piston and guide member relatively to the upper and lower inside surfaces of the casing.

4. In a door closer of the class described, a rectangular tubular casing adapted to be mounted in a hollow upper rail of a door and forming an internal longitudinal chamber having opposed flat sides, a rack within said chamber and having at one side thereof a bearing surface adapted to slide on one of the flat sides of the chamber, the teeth of the rack being formed at the opposed side of the rack, a piston adapted to slide in an opening in the casing communicating with said longitudinal chamber, means connecting the piston and rack, including means whereby said piston floats at one end of said rack while sliding with said rack in the casing, a guide member adapted to slide on the bottom fiat side of said chamber and supporting the opposed end of the rack to float in the chamber, a coil spring acting against said opposed end of said rack, a spring guide connected to the rack and extending in aligned relation to the coil spring, said guide member supporting the spring guide in position to hold the coil spring away from the sides of the casing chamber, a closer pinion mounted to rotate in the chamber in meshed relation to the rack,.and said closer pinion pressing the rack to hold its bearing surface against the said one side of the casing chamber as the rack floats on the piston and guide member relatively to the remaining sides of the chamber.

5. In a door closer of the class adapted to be mounted in a hollow upper rail of a door, an elongated casing having an internal longitudinal chamber formed with a longitudinal bearing surface, a rack within said casing chamber and having a bearing surface at one side thereof adapted to slide on the said longitudinal bearing surface of said casing chamber, the teeth of the rack being formed at the opposed side of the rack, a piston slidably mounted in the casing, means connecting said piston to one end of the said rack, including a spring yieldingly supporting said one end of the rack and on which said rack floats relatively to the piston, a guide member movable in said chamber and carried on the opposed end of the rack for floatingly supporting the opposed end of the rack in said chamber, a closer pinion rotatably mounted in said chamber in meshed relation to the teeth of the rack with the rack between the pinion and the longitudinal bearing surface of the chamber, and a part of the pressure incidental to the meshing of said closer pinion and rack being accepted by the bearing surface of said rack pressing against the longitudinal bearing surface of said chamber.

6. In a door closer of the class adapted to be mounted in a hollow upper rail of a door, an elongated casing having an internal longitudinal chamber formed with a flat vertical bearing surface extending longitudinally of said chamber, a rack within said casing chamber and having a vertical bearing surface at one side thereof adapted to slide on the said flat bearing surface of said casing chamber, the teeth of the rack being formed at the opposed side of the rack, a piston slidably mounted in the casing and secured to one end of the said rack, a guide member movable in said casing and carried on the opposed end of the rack, said piston and guide member supporting the rack for sliding in said chamber with said rack spaced from all surfaces of said chamber except said vertical bearing surface, a closer pinion rotatably mounted in said chamber in meshed relation to the teeth of the rack with the rack between the pinion and the fiat vertical bearing surface of the chamber, and a part of the pressure incidental to the meshing of said closer pinion and rack being accepted by the bearing surface of said rack pressing against the flat vertical bearing surface of said chamber.

7. In a door closer of the class described adapted to be mounted in a hollow upper rail of a door, an elongated casing having an internal longitudinal chamber formed with a flat vertical bearing surface extending longitudinally of said chamber, a rack having a vertical bearing surface adapted to slide on the flat bearing surface of said casing, a piston adapted to slide in an opening in said casing communicating with said longitudinal chamber, means connecting said piston to one end of the said rack, including a spring yieldingly supporting said one end of the rack and on which said rack floats relatively to the piston while sliding with said piston in the casing, a guide member movable in the casing and supporting the opposed end of the rack to float in the casing, a closer pinion rotating in the chamber in meshed relation to the rack with the rack between the pinion and the flat bearing surface of the chamber, and said closer pinion pressing the rack to hold its bearing surface against the flat bearing surface of the chamber as the rack floats on the piston and guide member relatively to the upper and lower inside surfaces of the chamber. 7

8. In a door closer of the class described adapted to be mounted in a hollow upper rail of a door, an elongated tubular casing having an internal longitudinal chamber formed with a flat vertical bearing surface extending longitudinally of said chamber, a rack having a vertical bearing surface adapted to slide on the flat bearing surface of said chamber, a piston adapted to slide in an opening in said casing communicating with said longitudinal chamber, means connecting said piston to one end of said rack, including a spring yieldingly supporting said one end of the rack and on which said rack floats relatively to the piston while sliding with said piston in the casing, a closer spring acting against the opposed end of the rack in said chamber, a guide member movable in the chamber and supporting said opposed end of the rack to float in the chamber, a closer pinion rotating in the chamber in meshed relation to the rack with the rack between the pinion and the vertical bearing surface of the chamber, and said closer pinion pressing the rack to hold its bearing surface against the flat bearing surface of the chamber as the rack floats on the piston and guide member relatively to the upper and lower inside surfaces of the chamber.

9. In a door closer of the class described, a rectangular tubular casing adapted to be mounted in a hollow upper rail of a door, a closer pinion mounted for rotation in the casing with the teeth at opposed sides of the pinion spaced a short distance relatively to two opposed vertical sides of the rectangular casing, a rack extending in the space between the pinion and one of said vertical casing sides and meshed with said pinion, said rack having a bearing surface adapted to slide on an inner flat surface of the said one vertical side of the rectangular tubular casing, a piston at one end of the rack and adapted to slide in the casing, means connecting the piston and rack whereby said piston slides with said rack, a guide member sliding on the bottom inner surface of the rectangular casing and supporting the opposed end of the rack in the casing, said piston and guide member supporting the rack in spaced relation to the top and bottom inner surfaces of the rectangular casing, and said closer pinion acting against the rack to press its bearing surface toward said one vertical side of the rectangular casing as the rack slides with the piston and guide member in the casing.

References Cited in the file of this patent UNITED STATES PATENTS 1,762,776 Gardner June 10, 1930 1,921,314 Garrison Aug. 8, 1933 1,989,908 Bohnsack et a1. Feb. 5, 1935 1,999,274 Bernhard Apr. 30, 1935 2,024,472 Norton Dec. 17, 1935 2,059,385 Morrissette Nov. 3, 1936 2,257,775 Zellers Oct. 7, 1941 2,381,233 Summers Aug. 7, 1945 2,472,620 Rhodes et al June 7, 1949 2,723,416 Schlage Nov. 15, 1955 

